A dark brown sandpiper with a strikingly white belly; in flight it appears almost black above with a sharply contrasting white rump. When unsettled it may bob its tail, though not as regularly as a Common Sandpiper. If flushed, it often rises steeply and flies fast with deep wingbeats, swooping in a swallow-like manner. It breeds in clearings and marshy spots within wet woodland, while migrants turn up in freshwater and brackish wetlands, especially along muddy edges of lakes and small ponds. Usually seen alone or in small groups, and seldom associating with other species.